1. Technical Field
The present invention relates to a technique of a head-mounted display device.
2. Related Art
A head-mounted display device (a head mounted display (HMD)), which is a display device mounted on a head, is known. For example, the head-mounted display device generates image light using a liquid crystal display and a light source and guides the generated image light to the eyes of a user using projection optical systems and light guide plates to thereby cause the user to visually recognize a virtual image. As the head-mounted display device, there are two types, i.e., a transmission type with which the user can visually recognize an outside scene in addition to the virtual image and a non-transmission type with which the user cannot visually recognize the outside scene. As the head-mounted display device of the transmission type, there are an optical transmission type and a video transmission type.
JP-A-2012-215673 (Patent Literature 1) describes a technique for switching information processing performed by an information processing apparatus according to intonation of voice serving as a form of an utterance. JP-A-2008-129412 (Patent Literature 2) describes an electronic apparatus that, after transmitting a control signal indicating announcement of sound to be output, adjusts timing of the output of the announced sound and outputs the sound. JP-A-2002-132804 (Patent Literature 3) discloses a technique with which an agent responds to, with registered content, content of an utterance of a specified user in a system including a server having stored therein contents of utterances of users registered in advance and contents of responses based on the contents of the utterances of the users. JP-A-2006-72992 (Patent Literature 4) describes a technique for displaying, as a text image, content of a response stored in advance to correspond to an utterance of a specified user in a system network including home electric appliances.
However, in the technique described in Patent Literature 1, when the processing is changed according to only the intonation of the voice, it is likely that the intonation of the voice is not correctly identified. In the techniques described in Patent Literatures 2 and 3, it is likely that a response intended by a user is not obtained. In the network described in Patent Literature 4, an image display unit, on which a character image is displayed, and an outside scene, which is an actual scene, are separately visually recognized by a user. There is no relation between the character image and the outside scene. Therefore, there is room of improvement in convenience of use of the network. Besides, in a technique of a head-mounted display device in the past, there has been a demand for a reduction in the size, a reduction in the costs, and the like of the head-mounted display device.